I was at 12.5 towing the XJ to and from R&V, avg. about 16-17 in the summer mixed driving. I have owned a few PSD's and never seen better than 18-19 Hwy. No way anyone gets 25+ unlesss it is all downhill.

I'm sorry your truck is such a piece of shit, but I am on an 8" spring lift with a 3" body lift, 44" boggers, a lund visor cap out front (of course to increase aerodynamics) and when I tow my 78 ft 5th wheel toy hauler (lifted to clear the bed rails of my lifted truck) with two jeeps on one tons inside I usually get 24 mpg towing.